1. Field of the Disclosure
Embodiments of the present disclosure relate to an input device in which an operation shaft is driven by operating an operation knob, and more specifically, it relates to an input device effectively used in a seat switch used for adjusting the posture of a vehicle seat.
2. Description of the Related Art
Until now, there has been widely known a power seat switch apparatus for a vehicle with which the position of a vehicle seat, the posture of a backrest, and the like can be electrically adjusted.
Examples of power seat switches for a vehicle include that disclosed in Japanese Unexamined Patent Application Publication No. 2004-288393. This power seat switch apparatus for a vehicle is provided with a driving body for selecting the position and posture of a seat, and an operation knob that rocks the driving body. A spherical engaging portion is formed at the tip of the driving body, this engaging portion is held by an engaging holding portion formed in the operation knob, and the operation knob can be smoothly moved relative to the driving body.
In general, a power seat switch apparatus for a vehicle is attached to the side surface of a seat. When operating an operation knob, operation is often performed without looking at the operation knob, while groping for the position of the operation knob.
When an operator gropes for the operation knob and operates it, the operator may strongly grasp part of the operation knob and may apply biasing force to the operation knob. Then, the operation knob may come off from a driving shaft.
In order to prevent the operation knob from coming off, it is conceivable to tightly fit the operation knob on the driving shaft. In that case, a load is applied to the movement of the operation knob, and the operation knob cannot be smoothly moved relative to the driving shaft.
These and other drawbacks exist.